Anaerobic digestion seen as possible emissions solution

Canadian farms could significantly reduce greenhouse gas emissions while generating renewable energy by converting agricultural waste into biogas, a McGill University doctoral student says.

Anjaly Paul said anaerobic digestion could transform livestock manure and crop residues that would otherwise decompose in landfills into valuable resources.

“What if we could use these leftovers to power a greenhouse, fuel a tractor or even replace synthetic fertilizers with organicones?”

Canada’s agriculture sector is being pushed by both consumers and policymakers to reduce greenhouse gas emissions. Much of that conversation has centred around farm efficiency, from 4R fertilizer management and precision agriculture to new products such as methane-reducing feed additive Bovaer or green ammonia production.

However, Statistics Canada still counts agriculture among the nation’s emissions drivers. Emissions were up between 1990and 2023, primarily due to increases in the oil and gas, transport and agriculture sectors, the agency reported.

Paul said anaerobic digesters could turn an environmental problem, such as manure and crop waste, into an environmental win.

In 2011, Canadian livestock produced almost 152 million tonnes of manure, with cattle accounting for 84 per cent, pigs eight per cent and poultry three per cent, Paul said. There’s also biological material from animal carcasses.